1. Field of the Invention
The present invention relates to a display system of colors in the color gamut of a display, and particularly to a high accuracy display system thereof.
2. Related Background Art
An RGB calorimetric system and an XYZ colorimetric system are well known as color systems. With the RGB colorimetric system, actually existing monochromatic light is used as primary stimuli to define existing colors by combining their primary stimulus values. Although capable of expressing colors in association with physical coloring materials, this colorimetric system has shortcomings such as presence of negative color-matching functions. Negative color-matching functions are inconvenient when designing actual optical equipments in that g=G/(R+G+B) on the chromaticity coordinate is broad but r=R/(R+G+B) is narrow.
Therefore, the XYZ colorimetric system which is free from the shortcomings of the RGB calorimetric system and is convenient for calculating color specification is defined as CIE-1931. Assuming that there is a linear relationship between the RGB calorimetric system and the XYZ colorimetric system, there is a relationship therebetween, which can be expressed by an equation (10) below.
Since it is assumed that a linear relationship exists between the RGB calorimetric system and the XYZ calorimetric system, which is apparent from the equation (10), conversion between RGB and XYZ has been performed linearly in a gradation range of 0 to 255, with the value 255 as the maximum luminance.
                              [                                                    X                                                                    Y                                                                    Z                                              ]                =                              [                                                            2.7689                                                  1.7518                                                  1.1302                                                                              1.0000                                                  4.5907                                                  0.0601                                                                              0                                                  0.0565                                                  5.5943                                                      ]                    ⁡                      [                                                            R                                                                              G                                                                              B                                                      ]                                              (        10        )            